As used herein the terms "cleaning" and "laundry" and their derivatives and counterparts refer to both dry cleaning (without water) and wet cleaning, and these terms may be used interchangeably to refer to both the act or process of washing and pressing and the things washed and the place where it is done. It is also contemplated that the method and apparatus of the present invention can be used to sort other items, such as uniforms, fabric samples, carpeting pieces, machined parts, tires, or the like. Furthermore, the present invention can be used in any industry where numerous items to be sorted can be identified by unique information and can be moved by the mechanisms of the invention. For the purpose of the present invention the items to be sorted are laundered garments hung on conventional wire hangers.
A commercial cleaner receives items to be cleaned from a number of different accounts. One account may be a large manufacturing facility with hundreds of workers, each having his or her own uniform or garment. A commercial cleaner normally cannot efficiently clean laundry or other items by handling items on a single account basis. The cleaning process is more efficient when the full capacity of machines is used requiring several accounts' items to be grouped together for cleaning. Thus, items from several accounts may be mixed and cleaned as a load to efficiently utilize cleaning equipment. Commercial laundry cleaning operations are successful because they process a large number of garments together in large machines.
Where the account is a facility that has a large number of garments being used by its workers, the garments must be arranged for delivery in some rational order so that workers are not spending inordinate time and effort locating their shirts or uniforms. Since the soiled garments are being returned to the same cleaners routinely for laundering, a means for identifying the garments can be attached permanently or removably to the garment. If affixed permanently, the cleaning operation does not have to attach new identification tags to the soiled garment every time it is received for cleaning. One means for identifying garments is by using conventional bar code strips affixed to the garments and read by a bar code reader. This identification system also eliminates the need for the individual account to sort soiled garments before being sent for cleaning.
In the uniform rental industry there normally is no invoice nor ticket to match. The identification information is permanently affixed to the garment, and the batches of laundry are kept together.
In the commercial cleaning of residential customers' garments, such as business shirts, a time consuming element of the sorting process is the step of separating the lot of cleaned items and assembling them with the appropriate ticket, remembering that a single ticket may contain several items of cleaning. Conventionally, a worker picks the first item in the lot off the rack, looks at the identifying data thereon, places the item with the appropriate ticket, and proceeds to the next item in the lot. This represents three opportunities for worker error. Because the cleaned items cannot be maintained in any particular order in the machines during cleaning, they must be sorted by hand by visually checking and pairing numbers after cleaning. Accordingly, it will be appreciated that it would be highly desirable to unite each item in a lot with their appropriate tickets without manually handling each item at each step of the reassembly process.
A problem associated with the sorting process that occurs after garments are laundered is that a worker must physically handle the tag to read the identification data which may consists of a four, five or even six or more digit number or combination of numbers and letters, creating an opportunity for error in reading the data. Even when being extremely careful, a worker is prone either to misread the identifying data or to transpose digits and thereby place a garment with the wrong ticket. The result of such an error is that an account receives the wrong item or no item at all.
Recently, several apparatus have been developed which automate, to a degree, the sortation process. U.S. Pat. No. 4,239,435, issued Dec. 16, 1980, to Weiss et al., discloses an apparatus and method for arranging a plurality of randomly arranged identifiable articles into a predetermined order. The apparatus includes a conveyor for releasably supporting the randomly arranged articles and for conveying the articles supported thereon past at least one receiving station arranged about the conveyor for receiving the articles. Identifying means are associated with the receiving station for identifying each article as it is conveyed past the receiving station. Release means responsive to the identifying means are provided for releasing the article identified by the identifying means from the conveyor means to the receiving station when the article identified is the next succeeding article in the predetermined order with respect to the articles previously received by the receiving station. Articles are only removed from the conveyor means when they are the next succeeding article in a predetermined order. The remaining articles will remain on the conveyor for subsequent passes past the receiving station. The method for arranging randomly arranged articles into a predetermined order comprises releasably supporting the randomly arranged articles on support means and moving the articles past at least one receiving station for receiving the articles. As each of the articles move past the receiving station, each article is released from the support means to the receiving station when the article is the next succeeding article in the predetermined order with respect to the articles previously received by the receiving station. The articles remaining on the support means continue moving past the receiving station until all of the articles on the support means are released to the receiving station.
Weiss et al. teaches that the garments are manually loaded onto a slow moving conveyor; only after all the garments are loaded can the apparatus speed up. Furthermore, the latch release mechanism which holds the wire hanger on the conveyor is very complex and mechanically inefficient. The apparatus requires a reference support position so that each of the receiving stations can initialize itself every rotation of the conveyor. Numerous rotations must be employed before all garments are removed by the receiving stations. In other words, because the garments are sorted linearly and in a single sortation conveyor system, a garment must travel around and around until the receiving station assigned to that garment is ready to receive it. This is likened to a card game of solitaire, where the player must deal cards from the deck repeatedly until the next playable card can be used. The deck must be replayed with all remaining cards until the appropriate numerical play can be made. It would be desirable for an automated apparatus to sort garments whereby the garment would be removed from the sorting machine to a receiving assembly within a single rotation. This would efficiently make room for more garments sooner.
Additionally, Weiss et al. must unload every garment from the conveyor onto the receiving stations before reloading a new batch. It would be desirable for an apparatus to automatically and continually accept and sort garments until the last garment to be sorted is loaded. Fewer operators would be required to supervise the operation.
U.S. Pat. No. 4,907,699, issued Mar. 13, 1990, to Butcher et al., discloses a method and apparatus for sorting and arranging garments in a selected order which have been sequentially placed in an unordered sequence. The garments are identified by a marking affixed to each garment, and each garment arranged in its identified sequence on a sorting conveyor having a multiplicity of movable carriers each for receiving a garment. Identification signals are rearranged in a preselected order, and a plurality of arranged signals are assigned to each one of a corresponding plurality of pick-off mechanisms positioned along the sorting conveyor. A computer calculates bidirectional movement of the sorting conveyor to minimize conveyor movement for positioning a garment for pick-off in its proper sequence by a respective one of the pick-off mechanisms. The conveyor is driven in a bidirectional mode to properly position the garment, and a pick-off mechanism is activated to remove the garment from the sorting conveyor and position the garment on an unloading conveyor. Each conveyor pick-off apparatus includes a fluid-powered cylinder inclined downward toward the sorting conveyor, and a drive unit for closing the carrier mechanism.
Butcher et al. requires the use of a reference marker to initialize the receiving assemblies for each rotation of the conveyor past the receiving stations. This system also uses a carousel that loads garments onto the conveyor. The carousel acts blindly, transferring every garment to the next position on the conveyor, regardless of order, and is not actively involved in the selective release of garments in a sortation operation. The carousel takes the place of a person in performing a simple transfer function, with little or no computer controlled selection commands.
Butcher et al. also uses a carrier mechanism on the carousel to transfer the garments to a very narrow numbered slot on a conveyor system that may hold hundreds of garments. The bidirectional conveyor motor must jockey back and forth to properly align the slot with the hanger, creating greatly increased wear on the motor. Extreme accuracy is needed by the conveyor stepping motor to index stop precisely at the carrier mechanism release point, otherwise the wire hanger will miss the appropriate slot. If a hanger should miss the numbered slot, its position will remain empty until all remaining shirts are loaded onto the conveyor and unloaded onto the receiving stations.
Understandably, it will be appreciated that it would be highly desirable to have a laundry sorting apparatus that is compact and does not require an enormous amount of floor space.